INVESTIGATION ON STRUCTURAL BEHAVIOUR OF GEOPOLYMER CONCRETE INFLUENCED BY MICRO SILICA AND STEEL FIBRE

CO2 is released into the atmosphere in amount equal to the production of Ordinary Portland Cement (OPC). Geopolymer concrete is an emerging technique in the construction field where OPC is totally replaced by Fly ash. Fly ash is a waste residue obtained from thermal power plant. Normally Class F fly ash based Geopolymer concrete requires elevated temperature curing (above 60◦C), which make them impossible for cast in situ construction. In this study the strength of geopolymer concrete is achieved by sunlight curing by addition of Class C fly ash and Micro silica. Sodium silicate solution (Na2SiO3) and sodium hydroxide solution (NaOH) with a ratio (Na2SiO3/ NaOH) of 2.5 is used as an activator for geopolymer concrete. Main objectives of the study are to investigate the effect of usability or replace ability of micro silica with steel fibre based geopolymer concrete instead of OPC concrete in structural applications. To achieve the goals, the optimum percentage of Micro silica, Class C fly ash and steel fibres are found. Compressive strength and split tensile tests are performed on specimens to evaluate the mechanical performance of the concrete.